Equipment Phase

An Equipment Phase Functions Much Like a Program.

 can be executed within any task, except for Safety tasks  contain and execute multiple routines, including normal subroutines, prestate routines, fault routines, or routines  containing the logic for different states of an equipment phase  can make use of the Max Scan and Last Scan timing functions  can have locally-scoped tags associated with them

Equipment Phase

Behavior of the Equipment Phase

 It is a state machine which that maps out how how the equipment phase operates.  The equipment phase enforces the transitions between states and executes the appropriate state routine.  When the equipment phase is in the Running state, it executes the Running routine. If it is in the Holding state, it executes the Holding routine.

Equipment Phase States and Transitions

Type Routine States

You can create state routines for any of the active states of the equipment phase. The active states include:  Aborting  Holding  Resetting  Restarting  Running  Stopping

Programming Phase Equipment Routines

You can write logic (i.e., code in RLL, SFC, STX, or FBD) for each state. This logic is referred to as phase logic. PhaseManager feature provides several instructions to support phase logic.

You do not have to implement every active state. A equipment phase, controller scoped tag with the same name as the equipment phase is created. This tag is of the PHASE data type and cannot be renamed or deleted. To further delineate this

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tag as an equipment phase tag, a ":Phase" is appended to the name. This tag contains information on the state, substate, owner, and other data related to the equipment phase. As the equipment phase executes, it updates this tag with its current state information.

Equipment Phase Tags

Sequencers

Applications and programs can control the execution of equipment phases by sending them commands. These applications are referred to as sequencers. There are four types of sequencers that can command an equipment phase:  Internal Sequencer – a Logix program that uses instructions to command the equipment phase  External Sequencer – a PC-based application that commands the equipment phase via CIP message  HMI – an RSView SE or ME station that commands the equipment phase via CIP.

 RSLogix 5000 – the command toolbar and phase monitor window send commands to the equipment phase

Sequencer Ownership

The equipment phase accepts commands from the sequencer type that is its current owner. A sequencer typically first takes ownership, then commands the equipment phase, and finally releases ownership. For more details on ownership, refer to the PATT and PDET instructions or the Monitoring and Commanding Equipment Phases section.

Input and Output Parameter Tags

Input and/or output parameter tags are configure to further modularize the equipment phase and to document the required or expected inputs and outputs. Parameter tags provide a mechanism for sequencers to store input values and retrieve output values while commanding the equipment phase. If the equipment phase has parameter tags, the sequencer typically performs the following operations:  Take ownership of the equipment phase  Write the input parameter values to the equipment phase ’ s tags  Command the equipment phase (e.g. Start)  Wait for the equipment phase to complete (or reach another

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state such as Stopped or Aborted)  Read the output parameter values from the equipment phase ’ s tags  Release ownership of the equipment phase